Well jet device for well testing and development and operating method for the well jet device

ABSTRACT

The invention relates to jet devices for extracting oil from wells and intensifying the oil influx rate. An output cone, a packer and a jet pump are mounted on a tubing string. One or several active nozzles are arranged inside the pump body, and a stepped pass channel provided with a mounting seat for a pressure-sealing unit which is disposed between stages and several channels for supplying a pumped-out medium are embodied inside said pump body. The axes of the nozzles are disposed in a parallel position with respect to the axis of the pass channel at a certain distance therefrom. The inventive device is provided with a radiator and a receiver-transducer of physical fields mounted on a cable in such a way that it is replaceable by other instruments. Said cable passes through the axial channel of the sealing unit which is arranged in such a way that it is successively replaceable by functional inserts such as a testing and depression inserts etc. Said inserts are provided with mechanisms for bringing them to the pump body and for extraction therefrom. Mounting seats for back valves and plugs are embodied in the lower part of the channels for supplying the pumped-out medium. The dimension ratios of the elements of the inventive device are also disclosed. The aim of the invention is to optimise the dimensions of the elements of said device and increase the performance thereof.

FIELD OF INVENTION

This invention relates to the field of pumping engineering, mainly towell jet devices for oil production and intensification of oil inflowfrom wells.

PRIOR ART

Known in the art is a well jet device comprising a jet pump installed onthe piping string in the well and a transmitter and areceiver-transducer arranged below the jet pump (RU 2129671 C1).

From the above source known is a method of operation of a well jetdevice, which includes lowering in the well a piping string with a jetpump, a packer and a transmitter and a receiver-transducer of physicalfields, the latter being arranged below the jet pump.

The known device and method enable to explore wells and pump variousextracted media, e.g., oil, out of wells, at the same time exploring thewell, the transmitter and receiver of physical fields being arrangedwith the possibility of moving back and forth along the well relative tothe jet pump and the stratum.

But in some cases this is insufficient for obtaining reliableinformation on the well condition, which reduces the efficiency of worksperformed in order to intensify oil production.

The closest, as to its technical essence and the achievable result, tothis invention in the part of the device as the object of the inventionis a well jet device for testing and developing wells, which comprises apacker, and a jet pump installed on the piping string, the body of thesaid pump comprising a stepped through passage with a mounting seatbetween steps for installing a sealing assembly with an axial passage,the said body of the well jet device being provided with severalmounting seats for installing plugs or active nozzles having mixingchambers and diffusers, the said device being provided with a wellpressure gauge, a sampling device and a flowmeter, all of them beinginstalled either on the sealing assembly or on a cable on the input sideof the jet pump for the pumped out medium (RU 2129672 C1).

Known from the same patent as the closest, as to its technical essenceand the achievable result, to this invention in the part of the methodis the method of operation of a well jet device, which includesinstallation, on the piping string, of a packer and a jet pump in thebody of which a through passage is made with a mounting seat, loweringof the whole assembly into the well, release of the packer andarrangement of well instruments below the jet pump.

The known well jet device and the method of operation of the well jetdevice enable to carry out various process operations in the well belowthe level at which the jet pump is installed, including those performedby lowering pressure difference above and below the sealing assembly.

But, the known well jet device and the method of operation do not enableto exploit the potential of the device in full due to non-optimalsequence of operations and dimension relations of various structuralelements of the well jet device.

DISCLOSURE OF INVENTION

The objective of this invention is to optimize the dimensions of variouscomponents of the construction of the well jet device and the sequenceof operations when carrying out works on intensifying the wellexploitation and, owing to it, to raise the efficiency of well jetdevice operation in developing and testing wells.

The stated objective in the part of the device as the object of theinvention is achieved owing to the fact that the well jet device fortesting and developing wells comprises, installed on the piping stringdown-top, an input cone with a shank, a packer with a through passageand a jet pump, in the body of which one or several active nozzles withthe respective mixing chambers and passages for supplying the activemedium are axially arranged and a stepped through passage is made with amounting seat between steps for installing a sealing assembly having anaxial channel, the said device being provided with a transmitter and areceiver-transducer of physical fields, which is arranged at the jetpump side for entry of the medium pumped out of the well and installedon a cable or a wire fed through the axial passage of the sealingassembly, the output of the jet pump is connected to the piping stringabove the sealing assembly, the input side of the jet pump passage forsupplying the pumped out medium is connected to the piping string belowthe sealing assembly, and the input side of the passage for supplyingthe working medium to the active nozzle is connected to the spacesurrounding the piping string, and in the body of the jet pump severalpassages for supplying the pumped out medium are made, the inputcross-section of the input cone is located not lower than the roof ofthe productive stratum, the total area of the cross-sections of thepassages for supplying the active medium is not less that the total areaof the output cross-sections of the active nozzles, the axis of eachactive nozzle is parallel to the axis of the through passage in the bodyof the jet pump and is located from the latter at the distance L beingnot less than 0.55 diameter D₁ of the bigger step in the through passagemade in the body of the jet pump or at the distance L being not lessthan 0.575 diameter D₂ of the lesser step in the through passage made inthe body of the jet pump and located below the mounting seat, thesealing assembly is movably arranged on the well-logging cable or a wirefed through the axial passage in the sealing assembly and installed withthe possibility of being alternatively replaced by the functionalinserts, namely, a hydrostatic testing insert, a depression insert, ablocking insert which is made with or without a bypass passage, aninsert for recording curves of stratum pressure restoration in theunder-packer space and an insert for hydrodynamic vibration impact onthe near-well zone of the productive stratum; the diameter D₃ of theaxial passage in the sealing assembly is not greater than 0.6 outerdiameter D₄ of the sealing assembly, the axes of the sealing assemblyand the functional inserts are aligned with the axis of the throughpassage in the jet pump; the functional inserts are made with thepossibility of installing below them autonomous well instruments as wellas have, in their upper part, a tool for delivery and removal of themfrom the body of the jet pump with the use of cable equipment, thewell-logging cable or wire are made with a cap for attaching wellinstruments, the sealing assembly being made with the possibility ofinstalling it on the well-logging cable or wire without disconnectingthe cap from them, the transmitter and receiver-transducer of physicalfields is connected to the cap of the well-logging cable with thepossibility of being replaced by other well instruments, e.g., aperforator, an ultrasonic transmitter, a thermometer, a pressure gauge,a flowmeter, a sampling device, which all may be lowered, either inturns or in one assembly, along the through passage of the jet pump bodyon the well-logging cable or wire into the well, the outer diameter D₅of the jet pump body is at least 2 mm less than the inner diameter D₆ ofthe casing string in the well where it is installed, the diameter D₄ ofthe sealing assembly is at least 1 mm less than the inner diameter D₇ ofthe piping string above the jet pump, the diameter D₈ of the transmitterand receiver-transducer of physical fields is at least 1 mm less thanthe diameter D₂ of the lower step of the through passage in the jet pumpbody and than the diameter D₉ of the through passage in the packer, thediameter D₁₀ of the well-logging cable or wire is at least 0.001 mm lessthan the diameter D₃ of the axial passage in the sealing assembly, andin the lower part of the passages for supplying the pumped out mediumpositions for installing check valves or plugs are made.

In the part of the method as the object of the invention the statedobjective is achieved owing to the fact that in the method of operationof the well jet unit in testing and developing wells consists ininstalling on the piping string, down-top, of an input cone with ashank, a packer and a jet pump in the body of which a stepped throughpassage with a mounting seat in made between the steps, lowering thatassembly into the well, arranging the input cone not below the roof ofthe productive stratum, then a transmitter and receiver-transducer ofphysical fields is lowered into the well and arranged below the jetpump, during lowering background measurements of temperature and otherphysical fields from the wellhead to the well bottom are taken, and thetransmitter and receiver-transducer of physical fields is removed fromthe well, then the packer is released, a blocking insert with a wellpressure gauge is dropped into the inner cavity of the piping string,the blocking insert being seated onto the mounting seat in the throughpassage, the said blocking insert separates the well area into the holeclearance and the space inside the piping string, then the packer ispressure-tested by way of supplying the working agent into the holeclearance, then the blocking insert is removed with the use of cableequipment, and the transmitter and receiver-transducer of physicalfields is lowered into the well together with the sealing assembly,which is movably arranged on the well-logging cable or wire above thecap on which the transmitter and receiver-transducer of physical fieldsis installed, the sealing assembly is installed onto the mounting seatin the through passage of the jet pump while ensuring the possibility ofback and forth motion of the well-logging cable or wire, then thetransmitter and receiver-transducer of physical fields is arranged inthe explored interval of the productive stratum, and, by supplying theworking medium to the active nozzle(s) of the jet pump, several valuesof pressure drawdown on the stratum are successively created, and, ateach value, bottom-hole pressures, the composition of the fluid comingfrom the stratum and the well flow rate are measured, after which theparameters of physical fields and those of bottom-hole pressure arerecorded when moving the transmitter and receiver-transducer of physicalfields along the well axis in the speed range from 0.1 to 100 meters perminute and at pressure drawdown values changing stepwise in the rangefrom 0.01 to 0.99 stratum pressure or at a set value of pressuredrawdown when the jet pump is either operated or shut down, then thetransmitter and receiver transformer of physical fields is lifted out ofthe well and at the same time physical fields from the input cone to thewellhead are registered, and the functional insert for recording curvesof stratum pressure restoration in the under-packer zone is lowered onthe well-logging cable or wire, the said insert being provided with apressure sensor and a sampling device, and installed in'the throughpassage of the jet pump, a required pressure drawdown on the stratum iscreated with the use of the jet pump, and, after sharp stopping ofsupplying the liquid working medium to the jet pump, a stratum pressurerestoration curve for the under-packer well zone is recorded, saidrecording of stratum pressure restoration curves may be done repeatedlyat different initial pressure drawdown on the stratum; after that theresults of exploration and testing the well are processed, and adecision is taken whether other repair works on the well are necessaryin order, e.g., to raise its productivity or ensure waterproofing, suchworks being conducted with the use of the assembly with the jet pump,which is in the well, as well as with the alternatively changedfunctional inserts as well as instruments lowered into the well with thesealing assembly on the well-logging cable or wire, e.g., a perforator,an ultrasonic transmitter, a sampling device, a powder-charge pressuregenerator, etc., in particular with the use of an ultrasonic transmitterthe stratum is impacted by acoustic waves in the pressure drawdown modein order to de-mud the productive stratum, by using an ultrasonicgenerator with frequency switching and selective acting upon, first,less permeable and, then, more permeable seams of the productivestratum, and an increase in the well output is monitored, and aftercompletion of the said works the cycle of well exploration is repeated.

The analysis of the well jet device has shown that the reliability andefficiency of its operation may be improved both by making variouscomponents of the device under strictly defined dimensions and bycarrying out works in the well in a strictly defined succession. Duringthe operation of the device different well modes are studied. It isrequired to install and remove the sealing assembly, to move thetransmitter and receiver-transducer of physical fields along the well.It has been found that it is advisable to make the diameter of thebigger step in the through passage, which is located above the mountingseat for the sealing assembly, at least 0.5 mm greater than the diameterof the step in the through passage, which is located below the mountingseat, and the diameter of the axial passage in the sealing assemblyshould not exceed 0.6 outer diameter of the sealing assembly, and, atthe same time, the diameter of the well-logging cable or wire should beat least 0.001 mm less than the diameter of the axial passage in thesealing assembly. In the result, the sealing assembly is securelyinstalled on the mounting seat and possible overflows through thesealing assembly are minimized. The arrangement of the active nozzleaxis at a distance not less than 0.55 diameter of the bigger step in thethrough passage or at a distance not less than 0.575 diameter of thelesser step in the through passage in the jet pump body, when making thenozzle axis parallel to the axis of the through passage, enables todetermine the least possible distance between the axis of the activenozzle and that of the through passage of the jet pump and,consequently, enables to determine the maximum permissible dimensions ofthe jet pump body that is of much importance, since the diameter of thewell is the main limiting factor when arranging equipment in the well.The possibility of replacing the sealing assembly with other functionalinserts and the possibility of placing, instead of the transmitter andreceiver-transducer of physical fields, other well instruments, inparticular a perforator, an ultrasonic transmitter, a sampling device, athermometer, a pressure gauge, etc., enables to conduct various works,e.g., to pressure-test the packer, transfer the well in the flow mode,conduct works on perforation of the productive stratum, its acidtreatment, waterproofing works and a number of other operations withoutlifting the jet pump and the piping string from the well. In the result,the possibilities of the well jet device in conducting studies andrepair and restoration works in the well are expanded and the timenecessary for such works is significantly shortened. Making of insertswith the axis aligned with the axis of the through passage, as well asmaking the outer diameter of the jet pump body at least 2 mm less thanthe inner diameter of the casing string, the diameter of the sealingassembly at least 1 mm less than the inner diameter of the piping stringabove the jet pump and the diameter of the transmitter andreceiver-transducer of physical fields at least 1 mm less than thediameter of the lower step in the through passage in the jet pump bodyand that of the through passage in the packer, enables to reduce thepossibility of inserts and instruments lowered into the well being stuckin the process of their installation or removal, which increases thereliability of operation of the well jet device. The arrangement of theinput cross-section of the input cone not lower than the roof of theproductive stratum enables to preclude to the maximum extent theinfluence of the shank on the registered physical fields in the intervalof the productive stratum.

Of no lesser importance is the rational organization of works aimed atexploring the well, which enable to obtain more adequate information onthe condition of the well and the productive stratum, and, due to it,accelerate the process of restoring the well output. In particular,background measurements of temperature and other physical fields in theoperation of lowering the transmitter and receiver-transducer ofphysical fields enable to get, prior to initiating inflow from thestratum, preliminary data on the present condition of the well, whichmakes it possible to elaborate practical measures for exploring the welland more adequately interpret the well exploration results in the modeof inflow from the stratum. Moving the transmitter andreceiver-transducer of physical fields along the well, especially in thearea of the productive stratum, both when the jet pump is operated orwhen it is shut down, enables to take dynamic and static characteristicsof the well. In the course of exploration it has been found thatadequate accuracy of obtained data may be obtained when moving thetransmitter and receiver-transducer of physical fields with the speedfrom 0.1 to 100 meters per minute and at changing bottom-hole pressurestepwise in the range from 0.99 stratum pressure to 0.01 stratumpressure or, at least, at one of the set values of pressure drawdown.The installation of the functional inserts enables, apart from theabove-stated possibilities, to organize different modes of welloperation, in particular, it becomes possible not only to get data onthe composition of the fluid coming from the productive stratum, butalso take important characteristics of the well, such as record astratum pressure restoration curve in the under-packer area, thispossibility being achieved due to reduction in the bottom-hole pressureup to a value being 0.01 of the stratum pressure and subsequent sharpstopping of supply of the liquid working medium to the nozzle of the jetpump, and, what is most important, the well jet device enables to makerecordings repeatedly at various modes in the above-stated range. As theresult, the reliability of the obtained data is significantly improved.Another specific feature of the method of operation of the well jetdevice is the possibility of complex impact on the productive stratum,in particular, perforation of the stratum and the subsequent impact onthe stratum with the use of an ultrasonic generator for creating a setlevel of pressure drawdown, which enables to perform the operation ofde-mudding the productive stratum efficiently. All the above-indicatedworks may be conducted without numerous re-installations of theequipment in the well, which improves the efficiency of the well jetdevice greatly. After the completion of a cycle of the works onexploring and restoring the well workability, the whole cycle may berepeated, also without the necessity to re-install the equipment in thewell. Thus, the scope of investigations carried out in the well has beenexpanded, which is of special importance when carrying out restorationworks.

In the result, the objective of the invention—to optimize the successionof operations and the dimensions of various components of the well jetdevice—has been achieved, and, owing to that, the efficiency ofoperation of the well jet device has been improved.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a longitudinal section of the well jet device describedherein.

FIG. 2 is a longitudinal section of the well jet body along A—A line.

FIG. 3 is a longitudinal section of the sealing assembly.

FIG. 4 is a longitudinal section of the well jet device with the sealingassembly installed in the through passage.

FIG. 5 is a longitudinal section of the well jet device with theblocking insert installed in the through passage.

FIG. 6 is a longitudinal section of the well jet device with thedepression insert and an autonomous instrument installed in the throughpassage.

PREFERRED EMBODIMENT OF THE INVENTION

The proposed well jet device for testing and developing wells, which isserved to implement the described method, comprises, installed on thepiping string 1 down-top, the input cone 2 with the shank 3, the packer4 with the through passage 5, and the jet pump 6, in the body 7 of whichone or several active nozzles 8 are axially arranged, with therespective mixing chamber 9 and the passage 10 for supplying the activemedium. In the body 7 of the jet pump 6 the stepped through passage 11is made with the mounting seat 12 between steps for installing thesealing assembly 13 having the axial channel 14. The said device beingprovided with the transmitter and receiver-transducer of physical fields15, which is arranged on the side of the jet pump 6 for entry of themedium pumped out of the well and installed on the cable or wire 16 fedthrough the axial passage 14 of the sealing assembly 13. The output sideof the jet pump 3 is connected to the piping string 1 above the sealingassembly 13. The input side of the passages 17 in the jet pump 6 forsupplying the pumped out medium is connected to the piping string 1below the sealing assembly 13, and the input side of the passage 10 forsupplying the working (active) medium to the active nozzle 8 (or theactive nozzles 8) is connected to the space surrounding the pipingstring 1. In the body 7 of the jet pump 6 several passages 17 are madefor supplying the pumped out medium. The input cross-section of theinput cone 2 is located at a distance h, not lower than the roof of theproductive stratum 18. The total area of the cross-sections of thepassages 10 for supplying the active medium is not less that the totalarea of the output cross-sections of the active nozzles 8. The axis ofeach active nozzle 8 is parallel to the axis of the through passage 11in the body 7 of the jet pump 6 and is located from the axis of thelatter at the distance L being not less than 0.55 diameter D₁ of thebigger step in the through passage 11 made in the body 7 of the jet pump6 or at the distance L being not less than 0.575 diameter D₂ of thelesser step in the through passage 11 made in the body 7 of the Jet pump6. The diameter D₁ of the bigger step, which is located below themounting seat 12, in the through passage 111 in the body 7 of the jetpump 6. The sealing assembly 13 is movably arranged on the well-loggingcable or wire 16 fed through the axial passage 14 in the sealingassembly 13 and installed with the possibility of being alternativelyreplaced by the functional inserts, namely, a hydrostatic testinginsert, a depression insert 19, a blocking insert 20 which is made withor without a bypass passage 21, an insert for recording curves ofstratum pressure restoration in the under-packer space and an insert forhydrodynamic vibration impact on the near-well zone of the productivestratum 18. The diameter D₃ of the axial passage 14 in the sealingassembly 13 is not greater than 0.6 outer diameter D₄ of the sealingassembly 13. The axes of the sealing assembly 13 and the functionalinserts are aligned with the axis of the through passage 11 in the body7 of the jet pump 6. The functional inserts are made with thepossibility of installing below them autonomous well instruments, e.g.,a well pressure gauge 22, as well as have, in their upper part, a tool23 for delivery and removal of them from the body 7 of the jet pump 6with the use of cable equipment. The well-logging cable or wire 16 aremade with a cap 26 for attaching well instruments. The sealing assembly13 is made with the possibility of installing it on the well-loggingcable or wire 16 without disconnecting the cap 26 from them, thetransmitter and receiver-transducer of physical fields being connectedto the cap 26 of the well-logging cable or wire 16 with the possibilityof being replaced by other well instruments, e.g., a perforator, anultrasonic transmitter, a thermometer, a pressure gauge, a flowmeter, asampling device, which all may be lowered, either alternatively or inone assembly, along the through passage 11 in the body 7 of the jet pump6 on the well-logging cable or wire 16 into the well. The outer diameterD₅ of the body 7 of the jet pump 6 is at least 2 mm less than the innerdiameter D₆ of the casing string 24 in the well where it is installed.The diameter D₄ of the sealing assembly 13 is at least 1 mm less thanthe inner diameter D₇ of the piping string 1 above the jet pump 6. Thediameter D₈ of the transmitter and receiver-transducer of physicalfields 15 is at least 1 mm less than the diameter D₂ of the lower stepof the through passage 11 in the body 7 of the jet pump 6 and than thediameter D₉ of the through passage 5 in the packer 4, the diameter D₁₀of the well-logging cable or wire 16 is at least 0.001 mm less than thediameter D₃ of the axial passage 14 in the sealing assembly 13. In thelower part of the passages 17 for supplying the pumped out medium thepositions 25 for installing check valves or plugs are made.

The described method of operation of the well jet device is implementedas follows.

First, the input cone 2 with the shank 3, the packer 4 and the jet pump6, in the body 7 of which the stepped through passage 11 with themounting seat 12 between the steps, are installed onto the piping string1. The whole assembly is lowered into the well, and the input cone 2 isarranged at a distance h not lower than the roof of the productivestratum 18. Then, the transmitter and receiver-transducer of physicalfields 15 is lowered into the well to a level below the jet pump 6. Whenbeing lowered into the well, the transmitter and receiver-transducer ofphysical fields 15 is used for background measurements of temperatureand other physical fields in the space from the wellhead to the wellbottom, after which it is removed from the well. Then the packer 4 isreleased, a blocking insert 20 with a well pressure gauge 22 is droppedinto the inner cavity of the piping string 1, the blocking insert 20being seated onto the mounting seat 12 in the through passage 11 in thebody 7 of the jet pump 6, the said blocking insert 20 separates the wellarea into the hole clearance and the space inside the piping string 1.Then the packer 4 is pressure-tested by way of supplying the workingagent into the hole clearance. Then the blocking insert 20 is removedwith the use of cable equipment, and the transmitter andreceiver-transducer of physical fields 15 is lowered into the welltogether with the sealing assembly 13, which is movably arranged on thewell-logging cable or wire 16 above the cap 26 on which the transmitterand receiver-transducer of physical fields 15 is installed. The sealingassembly 13 is installed onto the mounting seat 12 in the throughpassage 11 of the body 7 of the jet pump 6 while ensuring thepossibility of back and forth motion of the well-logging cable or wire16. After that, the transmitter and receiver-transducer of physicalfields 15 is arranged in the explored interval of the productive stratum18, and, by supplying the working medium to the active nozzle(s) 8 ofthe jet pump 6, several values of pressure drawdown on the stratum 18are successively created, and, at each value, bottom-hole pressures,compositions of the fluid coming from the stratum 18 and the well flowrate are measured. Then, the parameters of physical fields of theproductive stratum and the stratum fluid and those of the bottom-holepressures are recorded when moving the transmitter andreceiver-transducer of physical fields 15 along the well axis in thespeed range from 0.1 to 100 meters per minute and at pressure drawdownvalues changing stepwise in the range from 0.01 to 0.99 stratum pressureor at a set value of pressure drawdown when the jet pump 6 is eitheroperated or shut down. Then, the transmitter and receiver transformer ofphysical fields 15 is lifted out of the well and at the same timephysical fields from the input cone 2 to the wellhead are registered,and the functional insert for recording curves of stratum pressurerestoration in the under-packer zone is lowered on the well-loggingcable or wire 16, the said insert being provided with a pressure sensorand a sampling device, and installed in the through passage 11 in thebody 7 of the of the jet pump 6, a required pressure drawdown on thestratum 18 is created with the use of the jet pump 6, and, after sharpstopping of supplying the liquid working medium to the jet pump 6, astratum pressure restoration curve for the under-packer well zone isrecorded. Recording of stratum pressure restoration curves may be donerepeatedly at different initial pressure drawdown on the stratum 18.After that, the results of exploration and testing the well areprocessed, and a decision is taken whether other repair works on thewell are necessary in order, e.g., to raise its productivity or ensurewaterproofing, such works being conducted with the use of the assembly,being in the well, with the jet pump 6, as well as with thealternatively changed functional inserts as well as instruments loweredinto the well with the sealing assembly 13 on the well-logging cable orwire 16, e.g., a perforator, an ultrasonic transmitter, a samplingdevice, a powder-charge pressure generator, etc., in particular with theuse of an ultrasonic transmitter the stratum is impacted by acousticwaves in the pressure drawdown mode in order to de-mud the productivestratum 18, by using an ultrasonic generator with frequency switchingand selective acting upon, first, less permeable and, then, morepermeable seams of the productive stratum 18, and an increase in thewell output is monitored. After completion of the said works the cycleof well exploration is repeated.

INDUSTRIAL APPLICABILITY

This invention may be used in the oil industry for conducting repair andinsulation works, repair and restoration works as well as in testing anddeveloping wells in other industries where various liquid and gaseousmedia are extracted out of wells.

1. The well jet device for testing and developing wells, comprising,installed on a piping string down-top, an input cone with a shank, apacker with a through passage and a jet pump, in a body of which one orseveral active nozzles with their respective mixing chambers andpassages for supplying an active medium are axially arranged, and astepped through passage is made with a mounting seat between steps forinstalling a sealing assembly having an axial passage, said device beingprovided with a transmitter and a receiver-transducer of physicalfields, which is arranged at the jet pump side for entry of the mediumpumped out of the well and installed on a cable or a wire fed throughthe axial passage of the sealing assembly, the output of the jet pump isconnected to the piping string above the sealing assembly, the inputside of the jet pump passage for supplying pumped out medium isconnected to the piping string below the sealing assembly, and the inputside of the passage for supplying the working medium to active nozzle isconnected to space surrounding the piping string, and in the body of thejet pump several passages for supplying the pumped out medium are made,an input cross-section of the input cone is located not lower than theroof of a productive stratum, the total area of the cross-sections ofthe passages for supplying the active medium is not less that the totalarea of the output cross-sections of the active nozzles, the axis ofeach active nozzle is parallel to the axis of the through passage in thebody of the jet pump and is located from the latter at the distance Lbeing not less than 0.55 diameter D₁ of the bigger step in the throughpassage made in the body of the jet pump or at the distance L being notless than 0.575 diameter D₂ of the lesser step in the through passagemade in the body of the jet pump, the sealing assembly is movablyarranged on the well-logging cable or a wire fed through axial passagein the sealing assembly and installed with the possibility of beingalternatively replaced by the functional inserts, including at least oneof a hydrostatic testing insert, a depression insert, a blocking insertwhich is made with or without a bypass passage, an insert for recordingcurves of stratum pressure restoration in the under-packer space and aninsert for hydrodynamic vibration impact on the near-well zone of theproductive stratum; the diameter D₃ of the axial passage in the sealingassembly is not greater than 0.6 outer diameter D₄ of the sealingassembly, the axes of the sealing assembly and the functional insertsare aligned with the axis of the through passage in the jet pump; thefunctional inserts are adapted for installation thereon below autonomouswell instruments as well as have, in their upper part, a tool fordelivery and removal of them from the body of the jet pump with the useof cable equipment, the well-logging cable or wire are made with a capfor attaching well instruments, the sealing assembly is adapted forinstallation on the well-logging cable or wire without disconnecting thecap from them, the transmitter and receiver-transducer of physicalfields are connected to the cap of the well-logging cable replaceable byother well instruments, including, a perforator, an ultrasonictransmitter, a thermometer, a pressure gauge, a flowmeter, a samplingdevice, which all may be lowered, either in turns or in one assembly,along the through passage of the jet pump body on the well-logging cableor wire into the well, the outer diameter D₅ of the jet pump body beingat least 2 mm less than the inner diameter D₆ of the casing string inthe well where it is installed, the diameter D₄ of the sealing assemblybeing at least 1 mm less than the inner diameter D₇ of the piping stringabove the jet pump, the diameter D₈ of the transmitter andreceiver-transducer of physical fields being at least 1 mm less than thediameter D₂ of the lower step of the through passage in the jet pumpbody and than the diameter D₉ of the through passage in the packer, thediameter D₁₀ of the well-logging cable or wire being at least 0.001 mmless than the diameter D₃ of the axial passage in the sealing assembly,and in the lower part of the passages for supplying the pumped outmedium positions for installing check valves or plugs are made.
 2. Themethod of operation of the well jet unit in testing and developingwells, consisting of installing on a piping string, down-top, of aninput cone with a shank, a packer and a jet pump in a body of which astepped through passage with a mounting seat is made between the steps,lowering that assembly into a well, arranging the input cone not belowthe roof of a productive stratum, then lowering a transmitter andreceiver-transducer of physical fields into the well and arranged belowthe jet pump, during lowering, taking background measurements oftemperature and other physical fields from the wellhead to the wellbottom, and removing the transmitter and receiver-transducer of physicalfields from the well, then releasing the packer, dropping a blockinginsert with a well pressure gauge into the inner cavity of the pipingstring, the blocking insert being seated onto the mounting seat in thethrough passage, said blocking insert separating the well area into thehole clearance and the space inside the piping string, thenpressure-testing the packer by way of supplying working medium into thehole clearance, then removing the blocking insert with the use of cableequipment, and lowering the transmitter and receiver-transducer ofphysical fields into the well together with the sealing assembly, whichis movably arranged on the well-logging cable or wire above the cap onwhich the transmitter and receiver-transducer of physical fields isinstalled, installing a sealing assembly onto the mounting seat in thethrough passage in the body of the jet pump while ensuring thepossibility of back and forth motion of the well-logging cable or wire,then arranging the transmitter and receiver-transducer of physicalfields in the explored interval of the productive stratum, and, bysupplying the working medium to active nozzle(s) of the jet pump,successively creating several values of pressure drawdown on thestratum, and, at each value, measuring bottom-hole pressures, thecomposition of the fluid coming from the stratum and the well flow rateafter which, recording the parameters of physical fields and those ofbottom-hole pressure when moving the transmitter and receiver-transducerof physical fields along the well axis in the speed range from 0.1 to100 meters per minute and at pressure drawdown values changing stepwisein the range from 0.01 to 0.99 stratum pressure or at a set value ofpressure drawdown when the jet pump is either operated or shut down,then lifting the transmitter and receiver transformer of physical fieldsout of the well and at the same time physical fields from the input coneto a wellhead are registered, and lowering the functional insert forrecording curves of stratum pressure restoration in the under-packerzone on the well-logging cable or wire, said insert being provided witha pressure sensor and a sampling device, and installed in the throughpassage of the jet pump, creating a required pressure drawdown on thestratum with the use of the jet pump, and, sharply stopping of supplyingthe working medium to the jet pump and thereafter, recording a stratumpressure restoration curve for the under-packer well zone, saidrecording of stratum pressure restoration curves done repeatedly atdifferent initial pressure drawdown on the stratum, after thatprocessing the results of exploration and testing the well, and taking adecision whether other repair works on the well are necessary in order,to raise its productivity or ensure waterproofing, such works beingconducted with the use of the assembly with the jet pump, which is inthe well, as well as with alternatively changed functional inserts aswell as instruments lowered into the well with the sealing assembly onthe well-logging cable or wire, including at least one of a perforator,an ultrasonic transmitter, a sampling device, or a powder-chargepressure generator, in particular with the use of an ultrasonictransmitter the stratum is impacted by acoustic waves in the pressuredrawdown mode in order to de-mud the productive stratum, by using anultrasonic generator with frequency switching and selective acting upon,first, less permeable and, then, more permeable seams of the productivestratum, and monitoring an increase in the well output, and aftercompletion of the said works repeating the cycle of well exploration.